System-on-a-chip (SOC) designs involving mixed-signal virtual components (VCs) require integration with thousands of logic gates without noise interference. Meeting the challenges of this type of design, Dolphin Integration and NEC Electronics (Europe) recently created a Codec VC for audio and telecommunications applications.
The design successfully integrated A/D and D/A converters, programmable- gain functions and digital filters. Our effort resulted in some practical solutions to design problems, and demonstrated the deliverables needed for integrating mixed-signal VCs. Additionally, our experience led to some recommendations for the Virtual Socket Interface (VSI) Alliance “Analog/Mixed-Signal Virtual Socket Interface Extension” specifications.
A mixed-signal VC is formally defined as a macrocell integrating analog circuitry with logic functions managing finite-state signals, and implemented with gates. The Coline that we designed is typical of a complex mixed-signal VC. Basically, Coline is an analog front end for audio or telecommunications applications. Its compatibility with G714 UIT recommendations makes it suitable not only for fax and modern communications, but also for voice Codecs…
